Conventionally, in the field of image forming apparatus, calibration is performed commonly to maintain high image quality. For example, there is disclosed in JP-A-2004-252573 a configuration in which calibration can be performed with timing desired by a user. There is disclosed in JP-A-2000-190573 (U.S. Pat. No. 6,280,105 B1) a technique for prohibiting calibration even when the apparatus side determines that the calibration is necessary, if a user restricts execution of the calibration.
In recent years, printers have increasingly come to be used in such a form as to be network-connected via a LAN or the like and thereby be used by plural users. Therefore, in the configuration as described in JP-A-2004-252573 in which calibration can be started by a user, there is a probability that calibration is performed frequently or thoughtlessly by a large number of users. Performing calibration too frequently is not desirable because it generally causes deterioration of expendables and generates noise sound. There is another problem in that a hue, which has been used by a certain user as his or her favorite, is changed suddenly by calibration ordered by another user.
On the other hand, JP-A-2000-190573 discloses a technique for prohibiting, according to a user's request, calibration that the apparatus is going to perform automatically. However, this technique cannot solve the above problem that calibration may be performed frequently or thoughtlessly by a large number of users, because priority is given to a user's request.